Action Comics Vol 1 409
| StoryTitle3 = The Baffling Block of Metropolis | Synopsis3 = One morning, in Metropolis Park, a strange golden slab of unknown metal was discovered, having appeared overnight while the park was closed. Soon, the police was summoned to investigate. The man in charge of the operation, Capt. Horace Mitchell, disconfirms that the slab was a bomb. He also admits that the mystery should be left to Superman, but despite repeated appeals, he hasn't shown, leaving Capt. Mitchell to deal with the slab. Meanwhile, Superman himself is in the heart of Africa, tunnelling into a mountain in search of the world's largest diamond. Back in Metropolis, Capt. Mitchell tries using a cast-iron sledge hammer against the slab, but he only succeeds in denting the hammer. The police then use their rifles to blast the slab with "enough fire-power to knock over a giant redwood tree". The slab remains unharmed, leaving Mitchell to speculate that it may be an alien weapon designed to catch them off guard. He calls for the slab's removal, but the crane used to lift it snaps (it was only strong enough to lift 20 tons). Back in Africa, Superman finds the diamond and uses a combination of super-compression and heat vision to mold it into a compact, ultra-hard diamond. "This is vital to the super-job I have in mind!" he thinks to himself. Meanwhile, at Metropolis Park, Capt. Mitchell's efforts against the slab continue, using flames, bombs, and acid against it. A scientist argues that the slab may be a token of peace from an alien race, but as to why he's trying to destroy it, Capt. Mitchell could only state that he's doing his duty. At the end of the day, Superman finally shows up at the park. It is then revealed that Capt. Mitchell was on a secret request from Superman, explaining his attempts to crack the slab open. Superman had "forged the super-alloy out of alien elements he gathered from other planets", and trusted Capt. Mitchell to put the metal through an endurance test, having assisted him on police cases in the past. Capt. Mitchell confirms that the slab is impregnable, then asks what the slab is for. Superman says it is confidential, then takes the slab northward. His use for the diamond is revealed to be as a bit for a drill powered with super-strength, as even Superman himself can't penetrate the metal without help. He cuts away a keyhole with the drill and smooths out the edge with ultra-friction, thus completing his project: the door for his Fortress of Solitude. | Appearing1 = Featured Characters: * Supporting Characters: * Antagonists: * Other Characters: * Locations: * Items: * Vehicles: * | Appearing2 = | Appearing3 = Featured Characters: * Supporting Characters: * Horace Mitchell Antagonists: * None Other Characters: * An WGBS reporter * Scientist Locations: * ** *** Metropolis Park ** ** *** Items: * An ultra-hard diamond Vehicles: * None | Notes = | Trivia = | Recommended = | Links = }}